Information generation device, information generation method and program

Abstract

An information generation unit 30 acquires, from a polarization imaging unit 20, observation values in which polarization directions are at least three or more directions (m≥3). A noise amount calculation unit 35-1 calculates an amount of noise on the basis of an observation value in a first polarization direction. Similarly, noise amount calculation units 35-2 to 35-m calculate amounts of noise on the basis of observation values in second to m-th polarization directions. A polarization model estimation unit 36 estimates a polarization model by using the observation values for the respective polarization directions and the amounts of noise calculated by the noise amount calculation units 35-1 to 35-m. Thus, it is possible to calculate a polarization model that is robust against noise.

The invention claimed is: 
     
       1. An information generation device comprising:
 a noise amount calculation unit configured to calculate an amount of noise on a basis of a noise variance model estimated on a basis of an observation value for each polarization direction of a plurality of polarization directions; and 
 a polarization model estimation unit configured to estimate a polarization model by using the observation value and the amount of noise calculated by the noise amount calculation unit, wherein 
 the noise amount calculation unit and the polarization model estimation unit are each implemented via at least one processor. 
 
     
     
       2. The information generation device according to  claim 1 , further comprising
 a saturation detection unit configured to detect an observation value in a saturated state, wherein 
 the polarization model estimation unit is further configured to exclude the observation value in the saturated state and then estimates the polarization model, and 
 the saturation detection unit is implemented via at least one processor. 
 
     
     
       3. The information generation device according to  claim 2 , wherein
 the noise amount calculation unit is further configured to set a predetermined value as an amount of noise of the observation value in the saturated state in the saturation detection unit, and 
 the polarization model estimation unit is further configured to exclude the observation value in the saturated state due to that the amount of noise is set to the predetermined value and then estimates the polarization model. 
 
     
     
       4. The information generation device according to  claim 1 , further comprising
 a level correction unit configured to perform level correction of making the observation value for each of the plurality of polarization directions acquired for each of a plurality of drive modes uniform, wherein 
 the noise amount calculation unit is further configured to calculate the amount of noise by using the observation value corrected by the level correction unit, a correction gain used in the level correction, and the noise variance model, 
 the polarization model estimation unit is further configured to estimate the polarization model by using the observation value corrected by the level correction unit and the amount of noise calculated by the noise amount calculation unit, and 
 the level correction unit is implemented via at least one processor. 
 
     
     
       5. The information generation device according to  claim 4 , wherein
 the plurality of drive modes are drive modes having different sensitivities or exposure times. 
 
     
     
       6. The information generation device according to  claim 1 , wherein
 the observation value for each polarization direction of the plurality of polarization directions is an observation value in which the plurality of polarization directions are three or more directions. 
 
     
     
       7. The information generation device according to  claim 1 , further comprising
 a polarization imaging unit configured to acquire the observation value for each polarization direction of the plurality of polarization directions, wherein 
 the polarization imaging unit is implemented via at least one processor. 
 
     
     
       8. The information generation device according to  claim 7 , wherein
 the polarization imaging unit is further configured to store the noise variance model, and 
 the noise amount calculation unit is further configured to calculate the amount of noise by using the noise variance model stored in the polarization imaging unit. 
 
     
     
       9. An information generation device comprising:
 a noise amount calculation unit configured to calculate an amount of noise on a basis of an observation value for each of a plurality of polarization directions and a variance; and 
 a polarization model estimation unit configured to estimate a polarization model by using the observation value and the amount of noise calculated by the noise amount calculation unit, wherein 
 the noise amount calculation unit is further configured to calculate the amount of noise by using a noise variance model showing a relationship between the observation value and a variance, and 
 the noise amount calculation unit and the polarization model estimation unit are each implemented via at least one processor. 
 
     
     
       10. The information generation device according to  claim 9 , wherein
 the noise amount calculation unit is further configured to set a variance depending on the observation value as the amount of noise. 
 
     
     
       11. The information generation device according to  claim 9 , wherein
 the noise variance model is stored in advance in the noise amount calculation unit. 
 
     
     
       12. The information generation device according to  claim 9 , further comprising
 a noise variance model estimation unit configured to detect a plurality of observation areas from a captured image, obtain a variance from a plurality of observation values and an average observation value in each of the observation areas, and generate a noise variance model from average observation values and variances in the plurality of observation areas, wherein 
 the noise amount calculation unit is further configured to calculate the amount of noise by using the noise variance model estimated by the noise variance model estimation unit, and 
 the noise variance model estimation unit is implemented via at least one processor. 
 
     
     
       13. The information generation device according to  claim 12 , wherein
 the noise variance model estimation unit is further configured to set a flat area in the captured image as the observation area. 
 
     
     
       14. The information generation device according to  claim 12 , wherein
 the noise variance model estimation unit is further configured to set a still area in the captured image as the observation area. 
 
     
     
       15. An information generation method comprising:
 calculating an amount of noise on a basis of a noise variance model estimated on a basis of an observation value for each polarization direction of a plurality of polarization directions; and 
 estimating a polarization model by using the observation value and the amount of noise. 
 
     
     
       16. A non-transitory computer-readable medium having embodied thereon a program, which when executed by a computer causes the computer to execute an information generation method, the method comprising:
 calculating an amount of noise on a basis of a noise variance model estimated on a basis of the observation value for each polarization direction of a plurality of polarization directions; and 
 estimating a polarization model by using the observation value and the calculated amount of noise.